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Using Interactive Web Applications to Help Teach Math and Science Concepts: An Example from Signal Processing. Julie Greenberg January 20, 2005. Background. Biomedical Signal and Image Processing (HST582J/6.555J/16.456J) 25-35 students once/year (Spring term) Graduate level subject
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Using Interactive Web Applications to Help Teach Math and Science Concepts:An Example from Signal Processing Julie Greenberg January 20, 2005
Background • Biomedical Signal and Image Processing (HST582J/6.555J/16.456J) • 25-35 students once/year (Spring term) • Graduate level subject • mostly seniors and first-year grad students • Diverse backgrounds • HST, EECS, MechE, NucE, Aero/Astro • 90-minute lecture twice weekly • 4-hour software lab once per week
Initial Problem • Motivated by my frustration in teaching Fourier spectral analysis • Observed that students couldn’t apply lecture material in lab • Experience shared by my colleagues • Many students seemed to be overwhelmed by interaction of variables • Difficulty preparing examples for lecture
Initial solution • Developed a simulation/interactive demonstration to permit hands-on exploration of key variables in spectral analysis: • Select signal sources (sum of cosines, ECG, speech) • Select parameters (window length, window shape, DFT length) • Options to save and compare parameter sets • http://web.mit.edu/6.555/www/matweb/demo.html
New Problem/Concerns • We have the simulation. What do we do next? • What are advantages/disadvantages of this type of educational technology? • How do we make effective use of this educational technology in the context of the course? • Used alone, the simulation would likely have led to “fiddling” without much learning.
Overview of approach • Defined learning objectives and key concepts • Great value to having these stated explicitly • Implemented Legacy cycle • Reused/modified existing educational activities • Added new elements • Small group discussions • Interactive tutorial to guide students as they use the simulation to develop understanding of key concepts
Identified Learning Objectives • Student can analyze and interpret frequency content of biomedical signals • After completing this module, students should be able to: • analyze the effects of multiple variables on a frequency-domain representation • select parameters to perform frequency analysis of a signal, given desired specifications • interpret a given frequency-domain representation, given the parameters used • make inferences as to the parameter used, given a frequency-domain representation
Identified Key Concepts • Major Concept: • Fourier spectral analysis • Supporting concepts: • factors affecting amplitude resolution • factors affecting frequency resolution • effect of changing window length • effect of changing window shape • effect of changing DFT length • effect of changing multiple parameters simultaneously
Legacy Cycle: 1 of 4 • Initial Challenge • Design an electrocardiogram (ECG) monitor to detect life-threatening ventricular arrhythmias • 90-minute guest lecture on cardiac function • 15 minute introduction in lab
Legacy Cycle: 2 of 4 • Generate Ideas • Students brainstorm in groups of two • 30-40 minutes in lab • Multiple Perspectives • Class reconvenes in lab • Each group presents their ideas • Other students and instructor comment • Moderated discussion follows • 30-40 minutes in lab
Legacy Cycle: 3 of 4 • Research and Revise • Interactive tutorial on Web • Learning objectives and key concepts guided our generation of tutorial content • Series of questions that explore key concepts with immediate feedback • Guidance for using simulation • General text summaries of key concepts • Glossary, tables, figures • Optional hints and tips • Spectral analysis lecture – chalk and simulation
Legacy Cycle: 4 of 4 • Test your Mettle • students work in pairs to solve the ventricular arrhythmia challenge (entire four hour lab session during following week) • homework problem • Go Public • individual lab reports • quiz
Results • Students liked it • Survey data indicates strong positive reaction • Student learning improved • Study shows that students using the module demonstrated better understanding of key concepts than students not using module (JEE April 2003) • Instructor and TAs liked it • Extremely rewarding
Take Home Messages • Provide framework (e.g. web-based tutorial) to support students in making effective use of educational technologies • Identify learning objectives and key concepts • Strategic planning for teaching • Use HPL/Legacy cycle to deliver on learning objectives. • Provides overall structure so that elements (e.g. tutorial and simulation) are used in a pedagogically-informed context
Credits • Julie Greenberg, project leader • Dinh-Yen Tran, simulation software • Jeffrey Steinheider, simulation software • Natalie Smith, tutorial implementation • Tomas Lozano-Perez, tutorial software • Leonardo Cedolin, teaching assistant • Minnan Xu, teaching assistant • Sean Brophy, learning sciences consultant • Mark D’Avila, learning sciences consultant • Lori Breslow, learning sciences consultant • John Newman, assessment and evaluation consultant